18203620356 has 36 divisors (see below), whose sum is σ = 46130649292. Its totient is φ = 6052584384.

The previous prime is 18203620291. The next prime is 18203620373. The reversal of 18203620356 is 65302630281.

It is a happy number.

18203620356 is a `hidden beast` number, since 1 + 8 + 20 + 3 + 620 + 3 + 5 + 6 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 10482483456 + 7721136900 = 102384^2 + 87870^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 18203620356.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 622555 + ... + 651138.

Almost surely, 2^18203620356 is an apocalyptic number.

It is an amenable number.

18203620356 is an abundant number, since it is smaller than the sum of its proper divisors (27927028936).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18203620356 is a wasteful number, since it uses less digits than its factorization.

18203620356 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1274100 (or 1274095 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The spelling of 18203620356 in words is "eighteen billion, two hundred three million, six hundred twenty thousand, three hundred fifty-six".